Mastering audio for Soundcloud, iTunes, Spotify and Youtube

Why does my track sound different when I upload it to Soundcloud? How loud should I master my track for iTunes? What's the best volume level for music on YouTube? What does Spotify do to my track before it’s streamed back to listeners?

If you don’t know the answer to these questions your music might be affected when it’s presented to your fans. This post will give you the technical details to make sure your music sounds great on these platforms.

Most online platforms have a normalisation process. This makes the music play back at a consistent volume. When you hear a 'quietly mastered' jazz track followed by a 'loudly mastered' dubstep track they maintain a constant perceived loudness.

This is implemented so that the audience isn’t always reaching for the volume control, and its generally considered to be a great idea.

Before I get into the juicy details of this post, its important that you understand what the 'LUFS' system is. LUFS stands for 'loudness units relative to full scale'. Its the most accurate way to to measure loudness of audio. I think of it as a more precise RMS value.

Why does bouncing my master at a specific LUFS level help my music stand out on online platforms?

Lets take Spotify as our example. Spotify streams audio at around -14 LUFS. If a track has a loudness level of -8 LUFS, Spotify will decrease the volume of that track to -14 LUFS. If a track is -23 LUFS the volume will be increased to -14 LUFS.

This is GREAT news. It encourages artists to make their music more dynamic and less compressed. If you’re a producer, songwriter or artist you may have heard of the ‘Loudness War’.

The loudness war ideology is ‘the louder your track, the better it will sound to your listeners’. That is no longer necessarily the case. The Spotify scenario is explained further using pictures below.

Below in green we see a dynamic track measuring -16 LUFS. You can see just by looking at the waveform that the transients are all in tact and have plenty of room to breathe.

Below in red we see the same track but with compression and limiting bringing it up to -8 LUFS. See how the transients are now all squashed to the same level with no dynamic variation between them.

This makes the track sound much flatter and less interesting. -8 LUFS is the same loudness as chart topping hits such as Ellie Goulding ‘Love Me Like You Do’.

Below in red we see how the waveform would look when played back through Spotify. The track is streamed at around -14 LUFS which means the tracks overall volume is lowered, however the damage done by the excessive compression and limiting is irreversible.

This track will lack the charisma and energy of its more dynamic counterpart pictured in green at the beginning of the example.

Here we see the same track used in the examples above pictured side by side. They both have a loudness reading of -14 LUFS. The more dynamic bounce (green) will sound a lot better when played back through online streaming services.

Table Updated May 2017

Streaming Service

Playback Level

Apple Music *Soundcheck On*

~ 16 LUFS

YouTube

~ 13 LUFS

Spotify

~ 14 LUFS

Tidal

~ 14 LUFS

So how loud should I master my music?

You should master your music so it sounds great to you! These figures aren't 'targets', but it's worth remembering that:

1. Louder music can appear to sound 'better', so be sure to level-match your master when referencing your favourite mixes in the studio (we have an awesome plugin for that called REFERENCE, check it out!)

2. Your music will get turned down if it's louder than -14 LUFS. Going for a more dynamic and punchy mix will sound better than an over-compressed, distorted master. I personally like to keep my clients music no louder than around -8 short-term LUFS during the loudest part of the song when I'm mastering for Spotify.

3. Spotify suggests leaving at least -1dBTP (decibels true peak) of headroom when submitting music so they're optimised for the lossy formats. They suggest -2dBTP of headroom for loud track, as loud tracks have a greater chance of clipping during transcoding. Spotify streams audio using Ogg/Vorbis and AAC files which are almost guaranteed to increase the peak levels. For more info on true-peaks check out my post on How To Master Music To Get An Exact True Peak and LUFS Reading

How can I measure LUFS on my track?

Our plugin LEVELS has a number of features that will help you get a fantastic mix. One of these features is a LUFS meter located in the Headroom section under ‘LUFS’.

What is the best volume to use when submitting music to Soundcloud?

Soundcloud is different when it comes to loudness. Soundcloud doesn't normalise the volume playback on their tracks. But it's worth noting that they transcode all their audio to 128kbps MP3 for streaming. When the track is transcoded, some clipping and distortion can take place.

Louder tracks with higher peaks suffer the worst from the encoding and end up sounding crunchy and lacking clarity. Leave at least -1dBTP of headroom when mastering for Soundcloud and try not to go louder than -7 LUFS short-term.

Apples plugin ‘RoundtripAAC’ lets you preview how your track will sound in a lossy format. It will also tell you if your track will clip once it has been converted for streaming. RoundTripAAC converts to AAC rather than MP3 but it will give you a good reference.

CONCLUSION

There is no need to compress and limit your music to the max to ‘compete with other releases’. A dynamic and less squashed track will make your music stand out from the rest on online streaming platforms. Master your audio to a loudness that you feel best serves the music, but be aware that high peak levels and super-loud masters will give your listeners a sub-standard listening experience when they stream your audio.